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What Causes Dandruff? 4 Reasons Behind Scalp Condition

Facing the wrath of the flakes once again? If it is any consolation, you are not alone. Estimations suggest around 50 million people in the United States suffer from dandruff.

But what could be triggering or worsening the scalp condition? Here are four possible reasons you should know about.

1. Stress

"Stress can worsen any skin condition," says Dr. Lotika Singh, a dermatologist based in New York City. She explains that high levels of stress can impair your immune system which can often cause physical symptoms. The development of dandruff might be one of them.

"Particularly in the cases where the dandruff is itchy," Dr. Singh notes, is where stress can "perpetuate an itch-scratch cycle" i.e. the more a person scratches at their scalp, the itchier it becomes. And of course, another complication here is that stress levels could also flare up if a person experiences social and self-esteem problems while dealing with itchiness and visible dandruff.

2. Malassezia​

One of the most prevalent myths about dandruff is that the condition is caused by a dry scalp. But experts have countered this, stating one is more likely to have the problem if their scalp is too oily. This usually happens due to Malassezia yeasts which end up on the skin when oil is produced in excess.

"In some people, the yeast starts to feed on the excess oil and dead skin cells on the scalp, causing the skin cells to shed more frequently and clump into flakes," states dermatologist Jessica Wu, who is also an assistant professor at the University of Southern California Medical School.

3. Under-washing

How often do you wash your hair? Keep in mind that there is no right answer to this question since it depends on factors like skin type, hair type, styling products, etc. But if you do not pick up the shampoo bottle until your scalp becomes sore and your hair starts to look greasy, it may be a sign of under-washing which can promote flakes.

So the more you put off washing, the more excess dead skin cells start to pile up. When facing these signs, some people also make the mistake of using dry shampoo, says Dr. Francesca Fusco, a dermatologist and Dove hair expert. "What these people are really experiencing is dandruff. By not shampooing, you’re making the situation worse," she explains.

4. Allergy

Contact dermatitis is an allergic skin reaction when exposed to certain things like soap, latex, fragrances, jewelry, cosmetic products, or poison ivy. Since it is tied to itchiness, this reaction could also lead to the development of dandruff. If you often change your gels and sprays, it is possible that your skin is sensitive to one or more of the ingredients used in these styling products.

Certain treatments like permanent hair straightening could also trigger a reaction. On the list of potential allergens, the Mayo Clinic includes Formaldehyde, a harmful chemical which is might be used in some straightening processes.